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Speed up development, verify best performance and start up series production with confidence.

Doherty designs achieve high efficiency, greater linearity and increased output power. Get deep insight into your design with a dual-path, precisely synchronized source driving the Doherty amplifier and improve your yield.

Optimize Doherty power amplifiers

Your taskYou are responsible for developing a Doherty amplifier for a high-performance radio transmitter. Whether it is for 5G, SatCom or any other application demanding high per-formance and reproducibility, the challenges remain the same: ❙ How can you be sure that you are getting the maximum possible performance from the design?

❙ How can you evaluate its sensitivities and variations for series production?

Verification of 5G NR GaN Doherty amplifier maximum performance made

easy with the R&S®SMW200A vector signal generator and the R&S®FSW

signal and spectrum analyzer

Perfect Doherty drive conditions generated by the R&S®SMW200A and

AM/AM / AM/PM analysis with the R&S®FSW-K18 option

T&M solutionWith the R&S®SMW200A dual-path RF vector signal gen-erator, which perfectly addresses the dual-path architec-ture of the Doherty, and the R&S®FSW signal and spec-trum analyzer, you now have the toolkit you need to gain previously inaccessible insight into your design.

By performing a precise, repeatable and automated sweep of the amplifier inputs, you: ❙ Establish best-case performance of key parameters such as efficiency, linearity and power

❙ Make an informed choice regarding the best input architecture, especially for fixed RF input split

❙ Analyze the sensitivity of different design scenarios and understand how your design will perform in series production

Optimize_Doherty_power_amplifiers_ac_en_5216-0273-92_v0100.indd 1 11.07.2018 13:34:20

¸FSW signal and spectrum analyzer

¸SMW200A vector signal generator

Main power amplifier

Auxiliary power amplifier

Dohertycombiner

DUT

Rohde & Schwarz GmbH & Co. KG

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customersupport@rohde-schwarz.com

R&S® is a registered trademark of Rohde & Schwarz GmbH & Co. KG

Trade names are trademarks of the owners

PD 5216.0273.92 | Version 01.00 | July 2018 (sk)

Optimize Doherty power amplifiers

Data without tolerance limits is not binding | Subject to change

© 2018 Rohde & Schwarz GmbH & Co. KG | 81671 Munich, Germany 5216

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This rapidly acquired data provides you with previously in-visible insights for a well performing signal split design for dual-path Doherty.

You are assured of the highest possible performance from any set of devices no matter which of the following you use: ❙ Fixed RF input splitter ❙ Programmable RF splitter ❙ Dispersive input splitter ❙ Dual-input digital Doherty

Fixed RF split design sensitivity analysis

Explore your design’s performance capability, understand the trade-offs, prepare for production.

ApplicationRunning a test campaign while changing the drive signals in the two Doherty paths enables complete amplifier de-sign characterization.

The R&S®SMW200A vector signal generator outputs two signals whose relative linear (amplitude and phase) or non-linear (e.g. shaped) characteristics are varied with precision.

The R&S®FSW signal and spectrum analyzer not only re-turns scalar quantities such as spectral regrowth and EVM, but also AM/AM and AM/PM, gain and peak envelope power (using the R&S®FSW-K18 option).

Dual-input Doherty amplifier test setup with the R&S®SMW200A, the R&S®FSW and the DUT

Optimize_Doherty_power_amplifiers_ac_en_5216-0273-92_v0100.indd 2 11.07.2018 13:34:21